by bus or by plane for mitt romney and paul ryan this election could come down to one state. >> o.h. o.h.! works every time. >> reporter: ohio is one of the key swing states in this election and today romney and president obama will be battling for attention there, but the latest cbs news poll swing states shows romney with some ground to make up. the poll just out this morning has president obama up 10 points in the buckeye state, he had six point lead before the convention. >> we tried before, if it don't work, we don't like it, we're not going back. >> reporter: the numbers are similar in florida where the president has a nine point lead over romney and in pennsylvania he's maintained a double digit advantage for a couple of months now. but it's ohio that's been the main focus of the campaign. with president obama and his republican rival each making his 14th trip to the state. >> here in ohio -- >> reporter: turn on the tv in ohio and this is what you're likely to see. both campaigns spent more here than any other state. president obama and his allies have spent nearly $48 millio